SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b3320d580153cf734093dc2c654d5fb814f5133aa7281372df2136835e8cb6e2' 
  AND token = '7IRbkvjHv8sxyKxxzGWjwYqEKE/VDZ/EU4wgdJg7MMI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}